The present invention relates to non-hydrogenated or partially hydrogenated non-animal oils having a low level of trans-fatty acids and improved flavor and performance attributes especially suitable for food applications and processes for the preparation thereof.
As consumers have become more aware of the health impact of lipid nutrition, consumption of oils with high levels of unsaturated and polyunsaturated fats and low levels of trans-fats is desirable.
Many oils are chemically hydrogenated; hydrogenation is used to improve performance attributes such as stability. When an oil is hydrogenated, the number of olefinic unsaturations in the fatty acids is reduced. However, hydrogenation can affect the stereochemistry of double bonds by either moving the double bond to another position in the fatty acid or causing the primarily cis-double bonds to isomerize to trans-double bonds. Isomerization of cis-fatty acids to trans-fatty acids is undesirable due to the negative health issues relating to the consumption of trans-fatty acids.
One application of oils is for use during deep-frying. The temperatures of deep-frying can cause the oil to oxidize and thus, degrade faster than it would at a lower temperature. Thus, many unhydrogenated oils with high levels of unsaturated or polyunsaturated fats have limited use in deep-frying operations due to their instability; deep-frying is an important segment of the food processing industry. Many non-hydrogenated soybean oils are unstable and easily oxidized during cooking, which in turn creates off-flavors of the oil and compromises the sensory characteristics of foods cooked in such oils.
Polyunsaturated fatty acids (PUFAs) may be extracted from natural sources or synthesized by various organisms. However, there are several disadvantages associated with commercial production of PUFAs from natural sources. Natural sources of PUFAs, such as animals and plants, tend to have highly heterogeneous oil compositions. The oils obtained from these sources can require extensive purification to separate out one or more desired PUFAs or to produce an oil which is enriched in one or more PUFA. Fish oils containing significant quantities of EPA and DHA can have unpleasant tastes and odors, which would make them undesirable food ingredients or supplements. Furthermore, in some cases, fish oil capsules can contain low levels of the desired component and retain undesirable levels of other components, including contaminants.
PUFAs are considered to be useful for nutritional, pharmaceutical, industrial, and other purposes. Therefore, it is of interest to extract oils having high levels of PUFAs from genetically-modified seeds; these seeds have been modified to contain higher concentrations of SDA as compared to the corresponding naturally-occurring seed.